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USPS first class vs priority

USPS first class vs priority

USPS first class vs priority

What’s the difference between USPS priority mail and USPS first class? The main difference is in the size of the packages that can be delivered via each service. First class mail is limited to smaller packages that weigh less than 3.5 ounces, while priority mail can include packages that weigh up to 70 lbs.

In a general sense, first class is a service of letters/packages weighing less than 12 ounces. Priority mail is that same service for packages 12 ounces to 70 pounds.

That is the way that it originally was meant to work; priority mail was merely a differentiation between the weights of articles–they were handled the same, followed the same routes, and were delivered in the same amount of time.

However, since the Postal Service is a quasi-private business; they must take actions to make themselves competitive. Priority Mail has been a victim of that process.

First, if I recall correctly, they continued handling Priority the same as they always had, but they were marketing it as the “new” service that gave first class mail a higher priority than it previously had.

The Postal Service markedted it as a two to three day service anywhere in the country. That was a load of hoohah because first class mail had always had the imperative to take two to three days to go anywhere in the country.

Now, with the advent of flat rate envelopes, bags, and boxes; Priority Mail has become a somewhat different service. Plus, there is an International Priority Mail as well. When it all filters through all the hype, Priority Mail still comes down as plain old first class mail.

What’s the difference between USPS priority mail and USPS first class?

First Class Mail and Priority Mail and Priority mail differs in different aspects based on the weight, size, shape and delivery time of your package.

First Class Mail is used to ship parcels that are 13 ounces or less. Most commonly used in sending letters, thick envelopes and lightweight packages on a standard size. This type of mail is affordable.

Priority Mail is the type of mail preferable to be used by packages weighing up to 70lbs. From the word itself Priority speaks that all mail shipped through Priority mail will be prioritized to be delivered first. Priority mail is given priority over standard mail.

Heavier and bigger packages will be delivered using Priority Mail and smaller package as long as it won’t exceed in 13 ounces can be delivered by First Class Mail.

In terms of delivery both Priority Mail and First-Class Mail both arrived 1-3 days if a package is shipped to a domestic address. Priority Mail is convenient when you sent packages internationally as it cuts down shipping time notably.

However, delivery time differs according to Zones when you send a parcel domestically. Here is a chart showing the estimated delivery time of your parcel if sent domestically or internationally using First Class Mail and Priority Mail:

USPS first class vs priority
The USPS first class vs priority

USPS Package Intercept

USPS first class vs priority
USPS first class vs priority

Since priority mail delivers much faster it cost a little bit more expensive than First Class Mail.

Unfortunately, First Class Mail doesn’t have default insurance, unlike Priority Mail when in cases like your package was lost or damaged upon delivery you will be covered. Although First class mail has no default insurance they do allow for an extra charge for you to have additional insurance coverage.

Weight is the determining factor for this class of mail.

  • First Class Mail – 12 ounces or less
  • Priority Mail – 13 ounces or more up to 70 lbs (Note: Flat Rate Priority Mail boxes and envelopes can be used, and may hold items that weigh less than 13 ounces, but the rate paid for Priority Mail is for a minimum of 13 ounces. Since anything weighing less than 13 ounces can also be sent by First Class Mail, which is often faster than Priority Mail and costs less, one would normally consider that method first. Flat Rate Priority Mail boxes and envelopes are mostly for customer convenience when they are sending something weighing less than 13 ozs.)

While Priority Mail is faster than Standard Mail (packages, that is – not speaking of Standard advertising letter mail) due to the type of transportation used. Priority Mail will go by air but Standard Mail often goes by truck.

Neither are as fast as USPS First-Class letter mail, though Priority Mail sometimes can be as fast. The reason First-Class letter mail is faster is that it goes through high-speed sortation machines that can sequence it right down to the delivery address on a carrier’s route, while parcels of Priority Mail have to be sorted by an employee at the originating and delivery office, one by one.

USPS first class vs priority

The clue is the word “priority.” Priority mail is handled first. It’s marked so as to attract attention, and it’s the first piece to be grabbed off the belt when a sack of mail is dumped for sorting. At every step of the way, priority mail is treated with priority over regular first class mail.

If it’s Christmas time, and the truck is waiting to haul whatever is ready, the priority mail will be on that truck – other stuff may or may not be on that truck, and may or may not wait until the next day to ship.

Guaranteed timely delivery? Nope. If you want a money-back guarantee, buy Express Mail, which comes with a guarantee. If you just want it handled with priority over other mail, it’s Priority mail that you want to use. (It’s also worth noting that first-class mail over some particular weight will be just as cheap as USPS First Class, and so it becomes Priority by default.)

Compare Mail Services

Compare USPS mail services by Starting Price (retail and commercial), Ship Time, and more. Most services automatically include USPS Tracking, and you can purchase additional insurance and extra services.

First-Class Mail: Mail in 1–3 Business Days

First-Class Mail® is an affordable mail service for standard-sized, single-piece envelopes weighing up to 3.5 oz and large envelopes and small packages weighing up to 13 oz with delivery in 3 business days or less. From $0.55 at a Post Office.

USPS first class vs priority
USPS first class vs priority

USPS delivered to a wrong address

Why Is It Called First Class Mail?

First Class Mail may sound like it’s the top-tier service, and to a certain extent, it is. But this is not in comparison to Priority Mail. First Class Mail is a class of mail used to ship letters, thick envelopes, padded envelopes, and lightweight packages. First Class Mail is considered the top tier of mailed materials in comparison to:

  1. Second Class Mail: periodicals, magazines, newspapers that are printed more than 4 times a year.
  2. Third Class Mail: Marketing mail, flyers, mailers, etc.
  3. Fourth Class Mail: Media Mail (CDs, vinyl records, DVDs, books, bound print media consisting of 8 or more pages.)

Priority Mail Express: Overnight to 2-Day Guarantee

Our fastest domestic shipping service, Priority Mail Express® delivers 7 days a week, 365 days a year (with limited exceptions). Overnight delivery is available to most U.S. addresses and PO Boxes™2 with a money-back guarantee.

With our free Flat Rate Envelopes, you don’t need to weigh shipments 70 lbs and under. Purchase Priority Mail Express postage and shipping labels at a Post Office™ location or online. Prices start at $26.35.

Why Is It Called Priority Mail?

Priority Mail is the USPS’s class of mail that is their top priority to ship out. It delivers parcels at a quicker speed than First Class Mail and allows for far heavier parcels (up to 70 lbs).

Internationally, it is advantageous since it typically cuts shipping time down significantly. Because of this, it is a little bit more expensive than First Class Mail.

Priority Mail is also closer to UPS and FedEx services. However, it is frequently more economical than both UPS or FedEx for packages weighing under about 10 lbs.

This is generally because a USPS vehicle passes by addresses each day. Smaller parcels that can fit in a mailbox typically are economical.

If the parcel’s size/weight requires the delivery driver to leave their vehicle and/or are too large to fit in their messenger bag, then the price can begin to rise quickly.

Shipping in 1–3 Business Days

Priority Mail® is our bestselling mail service. Domestic deliveries arrive in 1-3 business days3 depending on where your package starts and where it’s going.

USPS first class vs priority
USPS first class vs priority

Tracking and insurance are included, shipping boxes and envelopes are free, and with Priority Mail Flat Rate®, you don’t need to weigh shipments 70 lbs and under. Purchase Priority Mail postage and shipping labels at a Post Office or online. Prices start at $7.70.

A major advantage of USPS Priority Mail is that it includes coverage in the event that a parcel becomes lost or damaged in transit. First Class Mail offers no default coverage, however, both Priority Mail and First Class Mail do allow additional coverage to be purchased through the USPS or through a third-party provider such as Shipsurance.

Media Mail: Shipping in 2–8 Business Days

Media Mail® is a cost-effective way to send media and educational materials. This service has restrictions on the type of media that can be sent. Prices start at $2.89 at a Post Office.

Media Mail
USPS first class vs priority

Using Media Mail

Here’s what you can send:

  • Books (at least 8 pages)
  • 16-millimeter or narrower width films
  • Printed music and test materials
  • Video and sound recordings
  • Playscripts and manuscripts
  • Printed educational reference charts
  • Medical loose-leaf pages and binders
  • Computer-readable media

NOTE: Video games, computer drives, and digital drives do not qualify for Media Mail prices.

Weight, Size, & Shape Requirements

  • Maximum weight is 70 lbs.

View Price Files

USPS Retail Ground

Shipping in 2–8 Business Days

USPS Retail Ground® is a reliable and economical way to ship less-than-urgent deliveries and oversized packages. Prices start at $7.70 at a Post Office.

Using Retail Ground

  • Includes USPS Tracking®
  • Good for packages too large for Priority Mail Express and Priority Mail delivery
  • Only available at USPS Post Offices

NOTE: Department of Defense employees overseas may send packages to the U.S. using Retail Ground through Click-N-Ship®. Sending Military & Diplomatic Mail

Weight, Size, & Shape Requirements

  • Retail Ground ships package up to 70 lbs and up to 130 inches in combined length and girth.
  • Dimensional (DIM) weight rates apply to large, lightweight p


First Class vs Priority Mail is a common decision ecommerce merchants make. But it’s easy to get the hang of. Generally speaking, anything under 16 oz should use First Class Mail and anything over 16 oz should ship with Priority Mail. There are a few exceptions, of course. And we’ll cover those exceptions later. But for domestic shipments—particularly clothing and apparel.

Basically, it’s the weight. First Class mail is almost entirely letters and flats (oversize letters) so they are processed and transported often from different facilities and may take a day longer in some cases.

Priority Mail is processed using large parcel sorting machines and transport is different because we try to get it there in two days. For two day delivery, trucks and planes can’t wait for First Class mail because it is often sorted in a building in another suburb.

Price Comparison
USPS first class vs priority

First Class often flies on regular passenger planes and Priority usually travels on cargo planes. Sometimes no difference. If you are mailing it local it’s gonna get there the next day for 48 cents anyway. Waste of money. But if you are sending something from coast to Coast the difference can be dramatic.

The PO uses FedEX planes to run the priority and express mail. You read that right. The overwhelming number of Priority mail gets delivered in 2 days.

First-class uses scheduled airlines and if under 500 miles trucks or trains. Using priority mail gets it delivered one to 2 days earlier on long-distance deliveries. It is also insured for 50 dollars and tracked.

USPS first class vs priority